IPv4 loopback address is missing, why?

[Len Conrad]

/etc/hosts :

::1 localhost.mydomain.tld localhost
127.0.0.1 localhost.mydomain.tld localhost


/etc/defaults/rc.conf :

ifconfig_lo0="inet 127.0.0.1"   # default loopback device configuration.

... but ifconfig always shows no inet:

lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
         inet6 fe80::1%lo0 prefixlen 64 scopeid 0x3
         inet6 ::1 prefixlen 128


so we added to /etc/rc.conf :

ifconfig_lo0="inet 127.0.0.1 netmask 255.0.0.0"

... still not inet4 loopback if (so commented it out).

no errors in /var/log/messages,
dmesg -a shows no error,
... other than services failing to grab ports on 127.0.0.1


thanks
Len